REDMOND, Wash., and CHICAGO, Dec. 4, 2001 — Microsoft Corp. (Nasdaq “MSFT”) and uBid, a leading online auction and e-commerce marketplace and majority-owned operating company of CMGI Inc. (Nasdaq “CMGI”), today announced a broad-based alliance that will create an enhanced user experience for the companies’ shared customers via Microsoft® .NET and the MSN®
network of Internet services. Highlights of the agreement include the following:

Naming uBid as the premier provider of content and products for the MSN Auctions Channel, due for launch in early December

uBid’s adoption of several key .NET technologies including .NET Passport, Microsoft’s popular single-sign-in authentication service, and .NET Alerts, which makes it easy for individuals to receive relevant information from Web sites, such as auction bid updates, any time, anywhere and on any device

Deployment of the Microsoft .NET Enterprise Servers to run uBid’s popular Web site and services, providing uBid with the world’s leading server platform for running XML-based Web services

Integration of uBid with the Microsoft bCentral (TM) small-business service called Commerce Manager, which provides uBid users with an even greater selection of products to choose from, while giving bCentral Commerce Manager customers another avenue to sell their products. bCentral is the leading Internet resource for Web-based business tools and applications for small businesses and offers an easy-to-use suite of services, based on the .NET Platform, specifically designed to help small companies better manage their everyday business processes

“The enhanced relationship with MSN underscores our great product offering and exposes users of MSN to uBid in more ways than ever,” said Tim Takesue, acting CEO of uBid. “Microsoft .NET technologies will enable our next generation of Web services, and through this agreement, MSN can now offer its audience an exciting array of leading brand-name products, while enabling uBid to continue to improve our customers’ experience.”

“Our alliance with uBid, a leading provider of auction-based services, not only allows us to provide our customers with leading brand name products on MSN Auctions, but also to empower them with additional tools, making it easier to buy and sell products within MSN,” said Yusuf Mehdi, vice president of MSN. “This agreement will help uBid cultivate new customer relationships through prominent placement across Microsoft properties and deepen existing ones with its adoption of .NET technologies.”

Deep Commitment to .NET

Recognizing .NET as the leading platform for developing and deploying Web services, uBid is making a deep commitment to Microsoft .NET,. For instance, uBid is extensively using Visual Studio® .NET and the .NET Framework to build its Web services, including an innovative application that will allow Windows®
XP users to manage their online auctions while working from their PCs — anywhere, any time. To get the best support for XML Web services, uBid is converting its entire Web site to .NET Enterprise Servers.

uBid also will add .NET Passport and .NET Alerts capabilities to its site, providing greater service and convenience to its customers. For those users who choose to do so, uBid will offer a secure and convenient single-sign in experience via a .NET Passport, thus reducing the amount of information to be remembered or retyped. Once signed into uBid through .NET Passport, uBid users can view important account information, sign up for the uBid Credit Card, or place a bid without having to re-enter their uBid login ID and password. The .NET Passport service is live on uBid today.

uBid customers also can choose to sign up for and receive relevant information on which they can act about their bids via .NET Alerts, which enables users to receive important messages through MSN Messenger Service or Windows Messenger as well as via e-mail and mobile devices. With .NET Alerts, uBid is able to provide immediate notification if a user is outbid or is a winner. Also, uBid will notify customers when the same product comes up for auction again. All these actions take place on the user’s behalf with their consent. .NET Alerts will be made available to uBid users in December.

About uBid

uBid, a majority-owned operating company of CMGI Inc., is a leading retail auction and e-commerce marketplace that offers consumers and businesses three ways to buy and sell. The company’s Internet auctions feature a rotating selection of more than 12,000 products daily in 16 different product categories, providing consumers and small to midsized businesses with the opportunity to purchase a wide range of brand-name merchandise, often at greatly reduced prices, through live-action bidding. Product categories include computers; computer peripherals; computer components; home office; housewares; sports and hobbies; jewelry and gifts; accessories; off-lease computers; consumer electronics; digital cameras and video; apparel and linens; home improvement; travel and events; collectibles; and everything else. In addition to uBid’s own auction listings or uBid Direct, uBid features uBid Preferred Partner auctions in which consumers will find products listed by uBid-approved businesses and backed by uBid or brand warranties. Users can also buy or sell products through uBid’s Consumer Exchange, in which consumers list their items for auction with no listing fee. With more than 3 million registered users, uBid is committed to providing its customers with the highest quality auction experience on the Internet and offers supplier warranties on most consumer products. uBid also meets Better Business Bureau Online standards, which gives customers the confidence and security to bid safely online. More information can be found at the company’s Web site at http://www.ubid.com/.

About Microsoft

Founded in 1975, Microsoft is the worldwide leader in software, services and Internet technologies for personal and business computing. The company offers a wide range of products and services designed to empower people through great software — any time, any place and on any device.

Microsoft, MSN, bCentral, Visual Studio and Windows are either registered trademarks or trademarks of Microsoft Corp. in the United States and/or other countries.

uBid and uBid.com are trademarks of uBid Inc.

The names of actual companies and products mentioned herein may be the trademarks of their respective owners.

This release contains forward-looking statements that address a variety of subjects including, for example, the expected benefits, features, functionality and offerings related to the agreement between uBid and Microsoft and the expected ability of uBid to auction products. The following important factors and uncertainties, among others, could cause actual results to differ materially from those described in these forward-looking statements: uBid’s success depends on the continued and increased acceptance of its Web site and the Internet as a medium; consumer preferences for the products offered by uBid may change rapidly; uBid’s technologies may not successfully interoperate with those of Microsoft or other third parties; and increased competition and technological changes in the markets in which uBid competes. For a detailed discussion of these and other cautionary statements, please refer to CMGI’s filings with the Securities and Exchange Commission, including CMGI’s most recent Annual Report on Form 10-K.

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